Journal Publications J127. E. Vlachos, C. Mavrokefalidis, K. Berberidis, and G. C. Alexandropoulos, "Spatially selective channel estimation for single-RF-chain beamforming with UAV-state feedback," IEEE Transactions on Vehicular Technology, under review, 2024. J126. A. D. Papadopoulos, Y. Ma, Q. Luo, and G. C. Alexandropoulos, "Adaptive polynomial chaos expansion for uncertainty quantification and optimization of horn antennas at subTHz frequencies," IEEE Transactions on Antennas and Propagation, under review, 2024. J125. Y. Zhou, X. Ma, Q. Luo, Y. Ma, G. C. Alexandropoulos, and X. Yang, "Wideband sub-THz reconfigurable intelligent surface using planar tightly coupled dipoles," IEEE Antennas and Wireless Propagation Letters, under review, 2024. J124. M. Bayraktar, N. González-Prelcic, G. C. Alexandropoulos, and H. Chen, "RIS-aided joint channel estimation and localization at mmWave under hardware impairments: A dictionary learning-based approach," IEEE Transactions on Wireless Communications, under review, 2024. J123. C. K. Sheemar, S. Solanki, G. C. Alexandropoulos, E. Lagunas, J. Querol, S. Chatzinotas, and B. Ottersten, "Full duplex joint communications and sensing for 6G: Opportunities and challenges," IEEE Wireless Communications, under review, 2024. J122. K. D. Katsanos, P. Di Lorenzo, and G. C. Alexandropoulos, "Multi-RIS-empowered multiple access: A distributed sum-rate maximization approach," IEEE Journal of Selected Topics in Signal Processing, under review, 2024. J121. E. Calvanese Strinati, G. C. Alexandropoulos, N. Amani, M. Crozzoli, G. Madhusudan, S. Mekki, F. Rivet, V. Sciancalepore, P. Sehier, M. Stark, and H. Wymeersch, "Towards distributed and intelligent integrated sensing and communications for 6G networks," IEEE Wireless Communications, under review, 2024. J120. A. L. Moustakas and G. C. Alexandropoulos, "MIMO MAC empowered by reconfigurable intelligent surfaces: Capacity region and large system analysis," IEEE Transactions on Wireless Communications, under review, 2024. J119. S. Nanchi, F. Liu, C. Masouros, G. C. Alexandropoulos, Y. Xiong, and Q. Zhang, "Secure ISAC MIMO systems: Exploiting interference with Bayesian Cramér-Rao bound optimization," EURASIP Journal on Wireless Communications and Networking, under review, 2024. J118. A. Mondal, D. Mishra, G. Prasad, and G. C. Alexandropoulos, "Multi-agent reinforcement learning for offloading cellular communications with multiple cooperating UAVs," IEEE Transactions on Intelligent Vehicles, under review, 2024. J117. P. Gavriilidis and G. C. Alexandropoulos, "Near-field beamforming for holographic MIMO communications: Theoretical analysis and tracking implementation," IEEE Transactions on Communications, under review, 2024. J116. A. Kunz, S. B. M. Baskaran, and G. C. Alexandropoulos, "Control channel lightweight security for ambient-powered programmable reflections via reconfigurable intelligent surfaces," IEEE Communications Standards Magazine, under review, 2024. J115. S. Ghosh, K. Singh, G. C. Alexandropoulos, C.-P. Li, and T. Q. Duong, "On the performance analysis of active STAR-RIS-aided multi-antenna based NGMA ISAC systems under imperfect SIC and CSI," IEEE Transactions on Communications, under revision, 2024. J114. E. Basar, G. C. Alexandropoulos, Y. Liu, Q. Wu, S. Jin, C. Yuen, O. Dobre, and R. Schober, "Reconfigurable intelligent surfaces for 6G: Emerging applications and open challenges," IEEE Vehicular Technology Magazine, under review, 2024. J113. H. Liu, J. An, G. C. Alexandropoulos, C. Yuen, D. W. K. Ng, and L. Gan, "DRL-based orchestration of multi-user MISO systems with stacked intelligent metasurfaces," IEEE Transactions on Wireless Communications, under review, 2024. J112. A. Ghaneizadeh, P. Gavriilidis, M. Joodaki, and G. C. Alexandropoulos, "Metasurface energy harvesters: State-of-the-art and their potential for sustainable reconfigurable intelligent surfaces," IEEE Access, under review, 2024. J111. F. Saggese, V. Croisfelt, R. Kotaba, K. Stylianopoulos, G. C. Alexandropoulos, and P. Popovski, "On the impact of control signaling in RIS-empowered wireless communications," IEEE Open Journal of the Communications Society, under revision, 2024. J110. T. Gong, L. Wei, C. Huang, G. C. Alexandropoulos, M. Debbah, and C. Yuen, "Near-field channel modeling for holographic MIMO communications," IEEE Wireless Communications, under revision, 2024. J109. E. Vlachos, A. Kaushik, Y. C. Eldar, and G. C. Alexandropoulos, "Time-domain channel estimation for extremely large MIMO THz communications with beam squint," IEEE Open Journal of the Communications Society, under revision, 2024. J108. R. Ghazalian, G. C. Alexandropoulos, G. Seco-Granados, H. Wymeersch, and R. Jäntti, "Joint 3D user and 6D hybrid reconfigurable intelligent surface localization," IEEE Transactions on Vehicular Technology, under revision, 2024. J107. A. Rabault, L. Le Magoarou, J. Sol, G. C. Alexandropoulos, N. Shlezinger, H. V. Poor, and P. del Hougne, "On the tacit linearity assumption in common cascaded models of RIS-parametrized wireless channels," IEEE Transactions on Wireless Communications, to appear, 2024. J106. J. Xu, L. You, G. C. Alexandropoulos, X. Yi, W. Wang, and X. Gao, "Near-field wideband extremely large-scale MIMO transmission with holographic metasurface antennas," IEEE Transactions on Wireless Communications, to appear, 2024. J105. S. Yadav, R. Gour, G. C. Alexandropoulos, and D. S. Gurjar, "Two-way communications empowered by reconfigurable intelligent surfaces: Outage analysis under hardware impairments and Nakagami-m fading," Physical Communications, to appear, 2024. J104. L. Wei, C. Huang, G. C. Alexandropoulos, Z. Yang, J. Yang, W. E. I. Sha, Z. Zhang, M. Debbah, and C. Yuen, "Tri-polarized holographic MIMO surface in near-field: Channel modeling and precoding design," IEEE Transactions on Wireless Communications, to appear, 2024. J103. Q. Li, M. Wen, E. Basar, G. C. Alexandropoulos, K. J. Kim, and H. V. Poor, "Cyclic-prefixed single-carrier transmission for RIS-empowered broadband wireless systems," IEEE Transactions on Wireless Communications, to appear, 2024. J102. R. Singh, A. Kaushik, W. Shin, G. C. Alexandropoulos, M. Toka, and M. Di Renzo, "Indexed multiple access with reconfigurable intelligent surfaces: The reflection tuning potential," IEEE Communications Magazine, vol. 62, no. 4, pp. 120–126, April 2024. J101. H. Kim, H. Chen, M. F. Keskin, Y. Ge, K. Keykhosravi, G. C. Alexandropoulos, S. Kim, and H. Wymeersch, "RIS-enabled and access-point-free simultaneous radio localization and mapping," IEEE Transactions on Wireless Communications, vol. 23, no. 4, pp. 3344–3360, April 2024. J100. S. Ghose, D. Mishra, S. P. Maity, and G. C. Alexandropoulos, "Jointly optimal RIS placement and power allocation for underlay D2D communications: An outage probability minimizing approach," IEEE Transactions on Cognitive Communications and Networking, vol. 10, no. 2, pp. 622–633, April 2024. J99. A. Masaracchia, D. V. Huynh, G. C. Alexandropoulos, B. Canberk, O. A. Dobre, and T. Q. Duong, "Towards the metaverse realization in 6G: Orchestration of RIS-enabled Smart wireless environments via digital twins," IEEE Internet of Things Magazine, vol. 7, no. 2, pp. 22–28, March 2024. J98. G. C. Alexandropoulos, N. Shlezinger, I. Alamzadeh, M. F. Imani, H. Zhang, and Y. C. Eldar, "Hybrid reconfigurable intelligent metasurfaces: Enabling simultaneous tunable reflections and sensing for 6G wireless communications," IEEE Vehicular Technology Magazine, vol. 19, no. 1, pp. 75–84, March 2024. J97. T. Gong, P. Gavriilidis, R. Ji, C. Huang, G. C. Alexandropoulos, L. Wei, M. Debbah, H. V. Poor, and C. Yuen, "Holographic MIMO communications: Theoretical foundations, enabling technologies, and future directions," IEEE Communications Surveys & Tutorials, vol. 26, no. 1, pp. 196–257, FIRST QUARTER 2024. J96. R. Ghazalian, H. Chen, G. C. Alexandropoulos, G. Seco-Granados, H. Wymeersch, and R. Jäntti, "Joint user localization and location calibration of a hybrid reconfigurable intelligent surface," IEEE Transactions on Vehicular Technology, vol. 73, no. 1, pp. 1435–1440, January 2024. J95. A. L. Moustakas, G. C. Alexandropoulos, and M. Debbah, "Reconfigurable intelligent surfaces and capacity optimization: A large system analysis," IEEE Transactions on Wireless Communications, vol. 22, no. 12, pp. 8736–8750, December 2023. J94. Q. Zheng, M. Wen, Q. Li, G. C. Alexandropoulos, and L. Xu, "Progressive channel estimation for single-carrier communications aided by reconfigurable intelligent surfaces," IEEE Wireless Communications Letters, vol. 12, no. 12, pp. 1993–1997, December 2023. J93. G. C. Alexandropoulos, D.-T. Phan-Huy, K. D. Katsanos, M. Crozzoli, H. Wymeersch, P. Popovski, P. Ratajczak, Y. Bénédic, M.-H. Hamon, S. Herraiz Gonzalez, P. Mursia, M. Rossanese, V. Sciancalepore, J.-B. Gros, S. Terranova, G. Gradoni, P. Di Lorenzo, M. Rahal, B. Denis, R. D'Errico, A. Clemente, and E. Calvanese Strinati, "RIS-enabled smart wireless environments: Deployment scenarios, network architecture, bandwidth and area of influence," EURASIP Journal on Wireless Communications and Networking, 103, pp. 1–38, October 2023. J92. J. He, A. Fakhreddine, C. Vanwynsberghe, H. Wymeersch, and G. C. Alexandropoulos, "3D localization with a single partially-connected receiving RIS: Positioning error analysis and algorithmic design," IEEE Transactions on Vehicular Technology, vol. 72, no. 10, pp. 13190–13202, October 2023. J91. S. Prabhakar Chepuri, N. Shlezinger, F. Liu, G. C. Alexandropoulos, S. Buzzi, and Y. C. Eldar, "Integrated sensing and communications with reconfigurable intelligent surfaces," IEEE Signal Processing Magazine, vol. 40, no. 6, pp. 41–62, September 2023. J90. B. Smida, A. Sabharwal, G. Fodor, G. C. Alexandropoulos, H. A. Suraweera, and C.–B. Chae, "Full-duplex wireless for 6G: Progress brings new opportunities and challenges," IEEE Journal on Selected Areas in Communications, vol. 41, no. 9, pp. 2729–2750, September 2023. J89. B. Smida, A. Sabharwal, G. Fodor, G. C. Alexandropoulos, H. A. Suraweera, and C.–B. Chae, "Guest editorial full duplex and its applications," IEEE Journal on Selected Areas in Communications, vol. 41, no. 9, pp. 2725–2728, September 2023. J88. L. Wei, C. Huang, G. C. Alexandropoulos, A. M. Elbir, Z. Yang, Z. Zhang, M. Di Renzo, M. Debbah, and C. Yuen, "Wireless communications empowered by reconfigurable intelligent surfaces: Model-based vs model-free channel estimation," Elsevier Journal of Information and Intelligence, vol. 1, no. 3, pp. 253–266, September 2023. J87. H. Chen, H. Kim, M. Ammous, G. Seco-Granados, G. C. Alexandropoulos, S. Valaee, and H. Wymeersch, "RISs and sidelink communications in smart cities: The key to seamless localization and sensing," IEEE Communications Magazine, vol. 61, no. 8, pp. 140–146, August 2023. J86. M. Rahal, B. Denis, K. Keykhosravi, M. F. Keskin, B. Uguen, G. C. Alexandropoulos, and H. Wymeersch, "Performance of RIS-aided nearfield localization under beams approximation from real hardware characterization," EURASIP Journal on Wireless Communications and Networking, 86, pp. 1–23, August 2023. J85. A. Mokh, G. C. Alexandropoulos, M. Kamoun, A. Ourir, A. Tourin, M. Fink, and J. de Rosny, "Iterative interference cancellation for time reversal division multiple access," IEEE Access, vol. 11, pp. 92788–92795, August 2023. J84. J. An, C. Xu, D. W. K. Ng, G. C. Alexandropoulos, C. Huang, C. Yuen, and L. Hanzo, "Stacked intelligent metasurfaces enabling efficient holographic MIMO communications for 6G," IEEE Journal on Selected Areas in Communications, vol. 41, no. 8, pp. 2380–2396, August 2023. J83. H. Choi, J. Chung, J. Oh, G. C. Alexandropoulos, and J. Choi, "WiThRay: A versatile 3D Ray-tracing simulator for smart wireless environments," IEEE Access, vol. 11, pp. 56822–56845, June 2023. J82. B. Yang, X. Cao, C. Huang, G. C. Alexandropoulos, L. Dai, C. Yuen, M. Debbah, and H. V. Poor, "Next generation reconfigurable metasurfaces: When wave propagation control meets computing," IEEE Wireless Communications, vol. 30, no. 3, pp. 120–128, June 2023. J81. K. Keykhosravi, B. Denis, G. C. Alexandropoulos, Z. S. He, A. Albanese, V. Sciancalepore, and H. Wymeersch, "Leveraging RIS-enabled smart signal propagation for solving infeasible localization problems," IEEE Vehicular Technology Magazine, vol. 18, no. 2, pp. 20–28, June 2023. J80. G. C. Alexandropoulos, K. D. Katsanos, M. Wen, and D. B. Da Costa, "Counteracting eavesdropper attacks through reconfigurable intelligent surfaces: A new threat model and secrecy rate optimization," IEEE Open Journal of the Communications Society, vol. 4, pp. 1285–1302, June 2023. J79. H. Zhang, N. Shlezinger, G. C. Alexandropoulos, A. Shultzman, I. Alamzadeh, M. F. Imani, and Y. C. Eldar, "Channel estimation with hybrid reconfigurable intelligent metasurfaces," IEEE Transactions on Communications, vol. 71, no. 4, pp. 2441–2456, April 2023. J78. J. He, A. Fakhreddine, and G. C. Alexandropoulos, "STAR-RIS-enabled simultaneous indoor and outdoor 3D localization: Theoretical analysis and algorithmic estimation," IET Signal Processing, vol. 17, no. 4, e12209, April 2023. J77. J. Xu, C. Yuen, C. Huang, N. Ul Hassan, G. C. Alexandropoulos, M. Di Renzo, and M. Debbah, "Reconfiguring wireless environment via intelligent surfaces for 6G: Reflection, modulation, and security," SCIENCE CHINA Inf. Sciences, vol. 66, no. 3, 130304, February 2023. J76. L. You, J. Xu, G. C. Alexandropoulos, J. Wang, W. Wang, and X. Gao, "Energy efficiency maximization of massive MIMO communications with dynamic metasurface antennas," IEEE Transactions on Wireless Communications, vol. 22, no. 1, pp. 393–407, January 2023. J75. R. Faqiri, C. Saigre-Tardif, G. C. Alexandropoulos, N. Shlezinger, M. F. Imani, and P. del Hougne, "PhysFad: Physics-based end-to-end channel modeling of RIS-parametrized environments with adjustable fading," IEEE Transactions on Wireless Communications, vol. 22, no. 1, pp. 580–595, January 2023. J74. G. C. Alexandropoulos, M. A. Islam, and B. Smida, "Full duplex massive MIMO architectures: Recent advances, applications, and future directions," IEEE Vehicular Technology Magazine, vol. 17, no. 4, pp. 83–91, December 2022. J73. G. C. Alexandropoulos, A. Mokh, R. Khayatzadeh, J. de Rosny, M. Kamoun, A. Ourir, A. Tourin, M. Fink, and M. Debbah, "Time reversal for 6G wireless communications: Novel experiments, opportunities, and challenges," IEEE Vehicular Technology Magazine, vol. 17, no. 4, pp. 74–82, December 2022. J72. M. A. Islam, G. C. Alexandropoulos, and B. Smida, "Joint analog and digital transceiver design for wideband full duplex MIMO systems," IEEE Transactions on Wireless Communications, vol. 21, no. 11, pp. 9729–9743, November 2022. J71. K. Chen-Hu, G. C. Alexandropoulos, and A. García Armada, "Differential data-aided beam training for RIS-empowered multi-antenna communications," IEEE Access, IEEE Access, vol. 10, pp. 113200–113213, October 2022. J70. K. Chen-Hu, G. C. Alexandropoulos, and A. García Armada, "Non-coherent modulation with random phase configurations in RIS-empowered cellular MIMO systems," ITU Journal on Future and Evolving Technologies, vol. 3, no. 2, pp. 1–14, September 2022. J69. G. C. Alexandropoulos, K. Stylianopoulos, C. Huang, C. Yuen, M. Bennis, and M. Debbah, "Pervasive machine learning for smart radio environments enabled by reconfigurable intelligent surfaces," IEEE Proceedings, vol. 110, no. 9, pp. 1494–1525, September 2022. J68. L. Wei, C. Huang, G. C. Alexandropoulos, W. E. I. Sha, C. Yuen, Z. Zhang, and M. Debbah, "Holographic MIMO surfaces for multi-user communications: Channel modeling and spectral efficiency analysis," IEEE Journal of Selected Topics in Signal Processing, vol. 16, no. 5, pp. 1112–1124, August 2022. J67. Y. Wang, Y. Peng, X. Liu, W. Li, G. C. Alexandropoulos, J. Yu, D. Ge, and W. Xiang, "DDU-Net: Dual-Decoder-U-Net for road extraction using high-resolution remote sensing images," IEEE Transactions on Geoscience and Remote Sensing, vol. 60, pp. 1–12, August 2022. J66. Y. Cheng, W. Peng, C. Huang, G. C. Alexandropoulos, C. Yuen, and M. Debbah, "RIS-aided wireless communications: Extra degrees of freedom via rotation and location optimization," IEEE Transactions on Wireless Communications, vol. 21, no. 8, pp. 6656–6671, August 2022. J65. L. Wei, C. Huang, Q. Guo, Z. Yang, Z. Zhang, G. C. Alexandropoulos, C. Yuen, and M. Debbah, "Joint channel estimation and signal recovery for RIS-empowered multi-user communications," IEEE Transactions on Communications, vol. 70, no. 7, pp. 4640–4655, July 2022. J64. X. Han, K. Xiao, R. Liu, X. Liu, G. C. Alexandropoulos, "Dynamic resource allocation schemes for eMBB and URLLC services in 5G wireless networks," Intelligent and Converged Networks, vol. 3, no. 2, pp. 145–160, June 2022. J63. G. C. Alexandropoulos, I. Vinieratou, and H. Wymeersch, "Localization via multiple reconfigurable intelligent surfaces equipped with single receive RF chains," IEEE Wireless Communications Letters, vol. 11, no. 5, pp. 1072–1076, May 2022. J62. R. Akif Tasci, F. Kilinc, E. Basar, and G. C. Alexandropoulos, "A new RIS architecture with a single power amplifier: Energy efficiency and error performance analysis," IEEE Access, vol. 10, pp. 44804–44815, May 2022. J61. V. Jamali, G. C. Alexandropoulos, R. Schober, and H. V. Poor, "Low-to-zero-overhead IRS reconfiguration: Decoupling illumination and channel estimation," IEEE Communications Letters, vol. 26, no. 4, pp. 932–936, Apr. 2022. J60. S. Barmpounakis, N. Alonistioti, G. C. Alexandropoulos, and A. Kaloxylos, "Dynamic infrastructure-as-a-service: A key paradigm for 6G networks and application to maritime communications," ITU Journal on Future and Evolving Technologies, vol. 3, no. 1, pp. 1–16, Apr. 2022. J59. X. Cao, B. Yang, C. Huang, G. C. Alexandropoulos, C. Yuen, Z. Han, and H. V. Poor, "Massive access of static and mobile users via reconfigurable intelligent surfaces: Protocol design and performance analysis," IEEE Journal on Selected Areas in Communications, vol. 40, no. 4, pp. 1253–1269, Apr. 2022. J58. M. Jian, G. C. Alexandropoulos, E. Basar, C. Huang, R. Liu, Y. Liu, and C. Yuen, "Reconfigurable intelligent surfaces for wireless communications: Overview of hardware designs, channel models, and estimation techniques," Intelligent and Converged Networks, vol. 3, no. 1, pp. 1–32, Mar. 2022. J57. G. C. Alexandropoulos, "Low complexity full duplex MIMO systems: Analog canceler architectures, beamforming design, and future directions," ITU Journal on Future and Evolving Technologies, vol. 2, no. 2, pp. 1–19, Dec. 2021. J56. E. Calvanese Strinati, G. C. Alexandropoulos, H. Wymeersch, B. Denis, V. Sciancalepore, R. D'Errico, A. Clemente, D.-T. Phan-Huy, E. De Carvalho, and P. Popovski, "Reconfigurable, intelligent, and sustainable wireless environments for 6G smart connectivity," IEEE Communications Magazine, vol. 59, no. 10, pp. 99–105, Oct. 2021. J55. I. Alamzadeh, G. C. Alexandropoulos, N. Shlezinger, and M. F. Imani, "A reconfigurable intelligent surface with integrated sensing capability," Nature Scientific Reports, vol. 11, no. 20737, pp. 1–10, Oct. 2021. J54. D. Selimis, K. P. Peppas, G. C. Alexandropoulos, and F. I. Lazarakis, "On the performance analysis of RIS-empowered communications over Nakagami-m fading," IEEE Communications Letters, vol. 25, no. 7, pp. 2191–2195, July 2021. J53. G. C. Alexandropoulos, N. Shlezinger, and P. del Hougne, "Reconfigurable intelligent surfaces for rich scattering wireless communications: Recent experiments, challenges, and opportunities," IEEE Communications Magazine, vol. 59, no. 6, pp. 28–34, June 2021. J52. L. Wei, C. Huang, G. C. Alexandropoulos, C. Yuen, Z. Zhang, and M. Debbah, "Channel estimation for RIS-empowered multi-user MISO wireless communications," IEEE Transactions on Communications, vol. 69, no. 6, pp. 4144–4157, June 2021. J51. C. Huang, Z. Yang, G. C. Alexandropoulos, K. Xiong, L. Wei, C. Yuen, and Z. Zhang, "Multi-hop RIS-empowered terahertz communications: A DRL-based hybrid beamforming design," IEEE Journal on Selected Areas in Communications, vol. 39, no. 6, pp. 1663–1677, June 2021. J50. J. Yuan, M. Wen, Q. Li, E. Basar, G. C. Alexandropoulos, and G. Chen, "Receive quadrature reflecting modulation for RIS-empowered wireless communications," IEEE Transactions on Vehicular Technology, vol. 70, no. 5, pp. 5121–5125, May 2021. J49. I. Yildirim, F. Kilinc, E. Basar, and G. C. Alexandropoulos, "Hybrid RIS-empowered reflection and decode-and-forward relaying for coverage extension," IEEE Communications Letters, vol. 25, no. 5, pp. 1692–1696, May 2021. J48. N. Shlezinger, G. C. Alexandropoulos, M. F. Imani, Y. C. Eldar, and D. R. Smith, "Dynamic metasurface antennas for 6G extreme massive MIMO communications," IEEE Wireless Communications, vol. 28, no. 2, pp. 106–113, April 2021. J47. Q. Li, M. Wen, S. Wang, G. C. Alexandropoulos, and Y.-C. Wu, "Space shift keying with reconfigurable intelligent surfaces: Phase configuration designs and performance analysis," IEEE Open Journal of the Communications Society, vol. 2, pp. 322–333, February 2021. J46. S. Lin, B. Zheng, G. C. Alexandropoulos, M. Wen, M. Di Renzo, and F. Chen, "Reconfigurable intelligent surfaces with reflection pattern modulation: Beamforming design, channel estimation, and achievable rate analysis," IEEE Transactions on Wireless Communications, vol. 20, no. 2, pp. 741–754, February 2021. J45. J. A. de Carvalho, D. B. da Costa, L. Yang, G. C. Alexandropoulos, R. Oliveira, and U. S. Dias, "User fairness in wireless powered communication networks with non-orthogonal multiple access," IEEE Wireless Communications Letters, vol. 10, no. 1, pp. 189–193, January 2021. J44. S. Lin, B. Zheng, G. C. Alexandropoulos, M. Wen, F.-J. Chen, and S. Mumtaz, "Adaptive transmission protocol for reconfigurable intelligent surface-assisted OFDM," IEEE Journal on Selected Areas in Communications, vol. 38, no. 11, pp. 2653–2665, November 2020. J43. C. Huang, S. Hu, G. C. Alexandropoulos, A. Zappone, C. Yuen, R. Zhang, M. Di Renzo, and M. Debbah, "Holographic MIMO surfaces for 6G wireless networks: Opportunities, challenges, and trends," IEEE Wireless Communications, vol. 27, no. 5, pp. 118–125, October 2020. (IEEE Communications Society Fred Ellersick Prize 2023) J42. G. C. Alexandropoulos, G. Lerosey, M. Debbah, and M. Fink, "Reconfigurable intelligent surfaces and metamaterials: The potential of wave propagation control for 6G wireless communications," IEEE ComSoc TCCN Newsletter, vol. 6, no. 1, June 2020. J41. K. P. Peppas, G. C. Alexandropoulos, E. D. Xenos, and A. Maras, "A simple and accurate statistical model for turbulence-induced fading in free-space optical systems," IEEE/OSA Journal of Lightwave Technology, vol. 38, no. 6, pp. 1286–1295, March 2020. J40. C. Xiang, S. Zhang, S. Xu, S. Cao, G. C. Alexandropoulos, and V. K. N. Lau, "Robust sub-meter level indoor localization with a single WiFi access point– Regression versus classification," IEEE Access, vol. 7, no. 1, pp. 146309–146321, December 2019. J39. H. Iimori, G. Abreu, and G. C. Alexandropoulos, "MIMO beamforming schemes for hybrid SIC FD radios with imperfect hardware and CSI," IEEE Transactions on Wireless Communications, vol. 18, no. 10, pp. 4816–4830, October 2019. J38. E. Vlachos, G. C. Alexandropoulos, and J. Thompson, "Wideband MIMO channel estimation for hybrid beamforming millimeter wave systems via random spatial sampling," IEEE Journal of Selected Topics in Signal Processing, vol. 13, no. 5, pp. 1136–1150, September 2019. J37. C. Huang, A. Zappone, G. C. Alexandropoulos, M. Debbah, and C. Yuen, "Reconfigurable intelligent surfaces for energy efficiency in wireless communication," IEEE Transactions on Wireless Communications, vol. 18, no. 8, pp. 4157–4170, August 2019. (IEEE Marconi Prize Paper Award in Wireless Communications 2021) J36. M. Di Renzo, M. Debbah, D.-T. Phan-Huy, A. Zappone, M.-S. Alouini, C. Yuen, V. Sciancalepore, G. C. Alexandropoulos, J. Hoydis, H. Gacanin, J. de Rosny, A. Bounceu, G. Lerosey, and M. Fink, "Smart radio environments empowered by AI reconfigurable meta-surfaces: An idea whose time has come," EURASIP Journal on Wireless Communications and Networking, 129, pp. 1–20, May 2019. (EURASIP Best Paper Award 2021) J35. M. Fozooni, H. Q. Ngo, M. Matthaiou, S. Jin, and G. C. Alexandropoulos, "Hybrid processing design for multipair massive MIMO relaying with channel spatial correlation," IEEE Transactions on Communications, vol. 67, no. 1, pp. 107–123, January 2019. J34. N. I. Miridakis, T. A. Tsiftsis, and G. C. Alexandropoulos, "MIMO underlay cognitive radio: Optimized power allocation, effective number of transmit antennas and harvest-transmit tradeoff," IEEE Transactions on Green Communications and Networking, vol. 2, no. 4, pp. 1101–1114, December 2018. J33. E. Vlachos, G. C. Alexandropoulos, and J. Thompson, "Massive MIMO channel estimation for millimeter wave systems via matrix completion," IEEE Signal Processing Letters, vol. 25, no. 11, pp. 1675–1679, November 2018. J32. D. Mishra and G. C. Alexandropoulos, "Transmit precoding and receive power splitting for harvested power maximization in MIMO SWIPT systems," IEEE Transactions on Green Communications and Networking, vol. 2, no. 3, pp. 774–786, September 2018. J31. D. Mishra, G. C. Alexandropoulos, and S. De, "Energy sustainable IoT with individual QoS constraints through MISO SWIPT multicasting," IEEE Internet of Things Journal, vol. 5, no. 4, pp. 2856–2867, August 2018. J30. K. P. Peppas, G. C. Alexandropoulos, P. T. Mathiopoulos, and J. Yang, "On the sum of ordered random variables and its applications to physical layer security of communication over η-μ fading channels with generalized selection combining," Transactions on Emerging Telecommunications Technologies, vol. 9, no. 6, pp. e3264, June 2018. J29. D. Mishra and G. C. Alexandropoulos, "Jointly optimal spatial channel assignment and power allocation for MIMO SWIPT systems," IEEE Wireless Communications Letters, vol. 7, no. 2, pp. 214–217, April 2018. J28. G. C. Alexandropoulos and K. P. Peppas, "Secrecy outage analysis over correlated composite Nakagami-m/Gamma fading channels," IEEE Communications Letters, vol. 22, no. 1, pp. 77–80, January 2018. J27. K. Cumanan, G. C. Alexandropoulos, Z. Ding, and G. K. Karagiannidis, "Secure communications with cooperative jamming: Optimal power allocation and secrecy outage analysis," IEEE Transactions on Vehicular Technology, vol. 66, no. 8, pp. 7495–7505, August 2017. J26. Y. Liu, L. Li, G. C. Alexandropoulos, and M. Pesavento, "Securing relay networks with artificial noise: An error performance based approach," MDPI Entropy 19: Special Issue on Network Information Theory, no. 8: 384, July 2017. J25. N. I. Miridakis, T. A. Tsiftsis, G. C. Alexandropoulos, and M. Debbah, "Simultaneous spectrum sensing and data reception for cognitive spatial multiplexing distributed systems," IEEE Transactions on Wireless Communications, vol. 16, no. 5, pp. 3313–3327, May 2017. J24. G. C. Alexandropoulos, P. T. Mathiopoulos, and P. Fan, "Performance analysis of L-branch scan-and-wait combining (SWC) over arbitrarily correlated Nakagami-m fading channels," IEEE Transactions on Vehicular Technology, vol. 66, no. 33, pp. 2868–2874, March 2017. J23. N. I. Miridakis, T. A. Tsiftsis, G. C. Alexandropoulos, and M. Debbah, "Green cognitive relaying: Opportunistically switching between data transmission and energy harvesting," IEEE Journal on Selected Areas in Communications, vol. 34, no. 12, pp. 3725–3738, December 2016. J22. Y. Peng, G. C. Alexandropoulos, and Y. Li, "Pilot-assisted channel estimation with MSE-optimal thresholding for OFDM systems," Transactions on Emerging Telecommunications Technologies, vol. 27, no. 8, pp. 1055–1070, August 2016. J21. G. C. Alexandropoulos, P. Ferrand, J.-M. Gorce, and C. B. Papadias, "Advanced coordinated beamforming for the downlink of future LTE cellular networks," IEEE Communications Magazine, vol. 54, no. 7, pp. 54–60, July 2016. J20. T. T. Duy, G. C. Alexandropoulos, T. T. Vu, N.-S. Vo, and T. Q. Duong, "Outage performance of cognitive cooperative networks with relay selection over double-Rayleigh fading channels," IET Communications, vol. 10, no. 1, pp. 57–64, January 2016. J19. K. Ho-Van, P. C. Sofotasios, G. C. Alexandropoulos, and S. Freear, "Bit error rate of underlay decode-and-forward cognitive networks with best relay selection," IEEE/KICS Journal of Communications and Networks, vol. 17, no. 2, pp. 162–171, April 2015. J18. G. C. Alexandropoulos and C. B. Papadias, "A reconfigurable iterative algorithm for the K-user MIMO interference channel," Signal Processing (Elsevier): Special Issue on Advances in Sensor Array Processing, vol. 93, no. 12, pp. 3353–3362, December 2013. J17. G. C. Alexandropoulos, P. C. Sofotasios, K. Ho-Van, and S. Freear, "Symbol error probability of DF relay selection over arbitrary Nakagami-m fading channels," HINDAWI Journal of Engineering, vol. 2013, Article ID 325045, 6 pages, 2013. J16. K. P. Peppas, G. C. Alexandropoulos, and P. T. Mathiopoulos, "Performance analysis of dual-hop AF relaying systems over mixed η-μ and κ-μ fading channels," IEEE Transactions on Vehicular Technology, vol. 62, no. 7, pp. 3149–3163, September 2013. J15. V. N. Q. Bao, T. Q. Duong, D. B. Da Costa, G. C. Alexandropoulos, and A. Nallanathan, "Cognitive amplify-and-forward relaying with best relay selection in non-identical Rayleigh fading," IEEE Communications Letters, vol. 17, no. 3, pp. 475–478, March 2013. J14. M. Matthaiou, G. C. Alexandropoulos, H. Q. Ngo, and E. G. Larsson, "Analytic framework for the effective rate of MISO fading channels," IEEE Transactions on Communications, vol. 60, no. 6, pp. 1741–1751, June 2012. J13. A. Papadogiannis, G. C. Alexandropoulos, A. G. Burr, and D. Grace, "Bringing mobile relays for wireless access networks into practice–Learning when to relay," IET Communications, vol. 60, no. 6, pp. 618–627, June 2012. J12. T. Q. Duong, V. N. Q. Bao, H. Tran, G. C. Alexandropoulos, and H.–J. Zepernick, "Effect of primary networks on the performance of spectrum sharing AF relaying," Electronics Letters, vol. 48, no. 1, pp. 25–27, January 2012. J11. G. C. Alexandropoulos, A. Papadogiannis, and P. C. Sofotasios, "A comparative study of relaying schemes with decode-and-forward over Nakagami-m fading channels," HINDAWI Journal of Computer Networks and Communications, vol. 2011, Article ID 560528, 14 pages, 2011. J10. T. Q. Duong, V. N. Q. Bao, G. C. Alexandropoulos, and H.–J. Zepernick, "Cooperative spectrum sharing networks with AF relay and selection diversity," Electronics Letters, vol. 47, no. 20, pp. 1149–1151, September 2011. J9. L. Jacobs, G. C. Alexandropoulos, M. Moeneclaey, H. Bruneel, and P. T. Mathiopoulos, "Analysis and efficient evaluation of the BER of OSTBCs with imperfect channel estimation in arbitrarily correlated fading channels," IEEE Transactions on Signal Processing, vol. 59, no. 6, pp. 2720–2733, June 2011. J8. T. Q. Duong, G. C. Alexandropoulos, H.–J. Zepernick, and T. A. Tsiftsis, "Orthogonal space-time block codes with CSI-assisted amplify-and-forward relaying in correlated Nakagami-m fading channels," IEEE Transactions on Vehicular Technology, vol. 60, no. 3, pp. 882–889, March 2011. J7. K. P. Peppas, G. C. Alexandropoulos, C. K. Datsikas, and F. I. Lazarakis, "Multivariate Gamma-Gamma distribution with exponential correlation and its applications in RF and optical wireless communications," IET Microwaves, Antennas & Propagation, vol. 5, no. 3, pp. 364–371, February 2011. J6. T. Q. Duong, G. C. Alexandropoulos, T. A. Tsiftsis, and H.–J. Zepernick, "Outage probability of MIMO AF relay networks over Nakagami-m fading channels," Electronics Letters, vol. 46, no. 17, pp. 1229–1231, August 2010. J5. G. C. Alexandropoulos and P. T. Mathiopoulos, "Performance evaluation of selection diversity receivers over arbitrarily correlated generalized Gamma fading channels," IET Communications, vol. 4, no. 10, pp. 1253–1265, June 2010. J4. G. C. Alexandropoulos, A. Papadogiannis, and K. Berberidis, "Performance analysis of cooperative networks with relay selection over Nakagami-m fading channels," IEEE Signal Processing Letters, vol. 17, no.5, pp. 441–444, May 2010. J3. G. C. Alexandropoulos, P. T. Mathiopoulos, and N. C. Sagias, "Switch-and-examine diversity over arbitrary correlated Nakagami-m fading channels," IEEE Transactions on Vehicular Technology, vol. 59, no.4, pp. 2080–2087, May 2010. J2. G. C. Alexandropoulos, N. C. Sagias, F. I. Lazarakis, and K. Berberidis, "New results for the multivariate Nakagami-m fading model with arbitrary correlation matrix and applications," IEEE Transactions on Wireless Communications, vol. 8, no. 1, pp. 245–255, Jan. 2009. J1. G. C. Alexandropoulos, N. C. Sagias, and K. Berberidis, "On the multivariate Weibull fading model with arbitrary correlation matrix," IEEE Antennas and Wireless Propagation Letters, vol. 6, pp. 93–95, 2007.   Preprints and Other Publications O6. RIS TECH Alliance, "Reconfigurable intelligent surface technology," White paper, March, 2023. O5. 5GPPP Test, Measurement and KPIs Validation Working Group, "Beyond 5G/6G KPIs and target values," White paper, 3 June, 2022. O4. K. Chen-Hu, G. C. Alexandropoulos, and A. G. Armada, "On the feasibility of a structured phase configuration search for RIS-assisted communications," COST, Bologna, Italy, 8–11 February 2022. O3. K. Chen-Hu, G. C. Alexandropoulos, and A. García Armada, "Non-coherent modulation for RIS-empowered multi-antenna OFDM communications," Online at arxiv.org, September 2018. O2. E. Calvanese Strinati, V. Sciancalepore, and G. C. Alexandropoulos, "RISE-6G: Reconfigurable intelligent sustainable environments for 6G wireless networks," European 5G Annual Journal, May 2021. O1. G. C. Alexandropoulos and M. Duarte, "Low complexity full duplex MIMO: Novel analog cancellation architectures and transceiver design," Online at arxiv.org, September 2018.   Conference Publications C142. J. He, A. Fakhreddine, and G. C. Alexandropoulos, "Millimeter wave cellular passive drone detection with reconfigurable intelligent surfaces," IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Valencia, Spain, 2–5 September 2024, under review. C141. S. Matos, Y. Ma, Q. Luo, J. Deuermeier, L. Lucci, P. Gavriilidis, A. Kiazadeh, V. Lain-Rubio, T. D. Phan, P. J. Soh, A. Clemente, L. M. Pessoa, and G. C. Alexandropoulos, "Reconfigurable intelligent surfaces for THz: Hardware impairments and switching technologies," International Conference on Electromagnetics in Advanced Applications and IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, Lisbon, Portugal, 2–6 September 2024, under review. C140. A. Paul, M. Katwe, K. Singh, G. C. Alexandropoulos, and C.-P. Li, "RIS-empowered 3D DoA estimation of multiple aerial targets via deep reinforcement learning," IEEE Vehicular Technology Conference Spring, Singapore, 24–27 June 2024, under review. C139. G. Stamatelis, A.-N. Kanatas, I. Asprogerakas, and G. C. Alexandropoulos, "Single- and multi-agent private active sensing: A deep neuroevolution approach," IEEE International Conference on Communications, Denver, USA, 9–13 June 2024, to be presented. C138. D. Wijekoon, A. Mezghani, G. C. Alexandropoulos, and E. Hossain, "Electromagnetically-consistent modeling and optimization of mutual coupling in RIS-assisted multi-user MIMO systems," IEEE International Conference on Communications, Denver, USA, 9–13 June 2024, to be presented. C137. H. Liu, J. An, D. W. K. Ng, G. C. Alexandropoulos, and L. Gan, "DRL-based orchestration of multi-user MISO systems with stacked intelligent metasurfaces," IEEE International Conference on Communications, Denver, USA, 9–13 June 2024, to be presented. C136. E. Calvanese Strinati, G. C. Alexandropoulos, M. Giyyarpuram, P. Sehier, S. Mekki, V. Sciancalepore, M. Stark, M. Sana, B. Denis, M. Crozzoli, N. Amani, P. Mursia, R. D’Errico, M. Boldi, F. Costanzo, F. Rivet, and H. Wymeersch, "Distributed intelligent integrated sensing and communications: The 6G-DISAC approach," Joint European Conference on Networks and Communications & 6G Summit 2024, Antwerp, Belgium, 3–6 June 2024, to be presented. C135. P. Gavriilidis, I. Atzeni, and G. C. Alexandropoulos, "Metasurface-based receivers with 1-bit ADCs for multi-user uplink communications," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Seoul, South Korea, 14–18 April 2024, pp. 1–5. C134. Y. Gabay, N. Shlezinger, T. Routtenberg, Y. Ghasempour, G. C. Alexandropoulos, and Y. C. Eldar, "Leaky waveguide antennas for downlink wideband THz communications," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Seoul, South Korea, 14–18 April 2024, pp. 1–5. C133. I. Gavras, I. Atzeni, and G. C. Alexandropoulos, "Near-field localization with 1-bit quantized hybrid A/D reception," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Seoul, South Korea, 14–18 April 2024, pp. 1–5. C132. I. Gavras and G. C. Alexandropoulos, "Joint near-field target tracking and communications with full duplex holographic MIMO," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Seoul, South Korea, 14–18 April 2024, pp. 1–5. C131. G. C. Alexandropoulos, A. Clemente, S. Matos, R. Husbands, S. Ahearne, Q. Luo, V. Lain-Rubio, T. Kürner, and L. M. Pessoa, "Reconfigurable intelligent surfaces for THz: Signal processing and hardware design challenges," in Proc. European Conference on Antennas and Propagation, Glasgow, Scotland, 17–22 March 2024, pp. 1–5. C130. A. D. Papadopoulos, Y. Ma, Q. Luo, and G. C. Alexandropoulos, "Adaptive polynomial chaos expansion for uncertainty quantification of subTHz horn antennas with flat-top radiation patterns," in Proc. European Conference on Antennas and Propagation, Glasgow, Scotland, 17–22 March 2024, pp. 1–5. C129. X. Ma, Y. Zhou, Q. Luo, Y. Ma, K. Stylianopoulos, and G. C. Alexandropoulos, "1-Bit sub-THz RIS via planar tightly coupled dipoles: Beam shaping and proof of concept," in Proc. European Conference on Antennas and Propagation, Glasgow, Scotland, 17–22 March 2024, pp. 1–5. C128. S. Yadav, R. Gour, G. C. Alexandropoulos, and D. S. Gurjar, "Performance analysis of RIS-aided two-way communications under hardware impairments and Rayleigh fading," in Proc. IEEE International Conference on Advanced Networks and Telecommunications Systems, Jaipur, India, 17–20 December 2023, pp. 1–6. C127. K. Stylianopoulos, M. Bayraktar, N. González-Prelcic, and G. C. Alexandropoulos, "Autoregressive attention neural networks for non-line-of-sight user tracking with dynamic metasurface antennas," in Proc. IEEE Workshop on Computational Advances in Multi-Sensor Adaptive Processing, Los Sueños, Costa Rica, 10–13 December 2023, pp. 1–5. C126. M. Talha, B. Smida, G. C. Alexandropoulos, and M. A. Islam, "Multi-target two-way integrated sensing and communications with full duplex MIMO radios," in Proc. IEEE Asilomar Signals, Systems and Computer Conference, Pacific Grove, USA, 29 October–1 November 2023, pp. 1–5. C125. K. D. Katsanos and G. C. Alexandropoulos, "Spatial secrecy spectral efficiency optimization enabled by reconfigurable intelligent surfaces," in Proc. European Signal Processing Conference, Helsinki, Finland, 4–8 September 2023, pp. 1–5. C124. F. Zhu, B. Wang, Z. Yang, C. Huang, Z. Zhang, G. C. Alexandropoulos, C. Yuen, and M. Debbah, "Robust holographic mmWave beamforming by self-supervised hybrid deep learning," in Proc. European Signal Processing Conference, Helsinki, Finland, 4–8 September 2023, pp. 1–5. C123. C. K. Sheemar, G. C. Alexandropoulos, D. Slock, J. Querol, and S. Chatzinotas, "Full-duplex-enabled joint communications and sensing with reconfigurable intelligent surfaces," in Proc. European Signal Processing Conference, Helsinki, Finland, 4–8 September 2023, pp. 1–5. C122. I. Gavras, M. A. Islam, B. Smida, and G. C. Alexandropoulos, "Full duplex holographic MIMO for near-field integrated sensing and communications," in Proc. European Signal Processing Conference, Helsinki, Finland, 4–8 September 2023, pp. 1–5. C121. I. Alamzadeh, G. C. Alexandropoulos, and M. F. Imani, "Intensity-only OMP-based direction estimation for hybrid reconfigurable intelligent surfaces," in Proc. IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, Portland, USA, 23–28 July 2023. C120. K. Stylianopoulos, M. Merluzzi, P. Di Lorenzo, and G. C. Alexandropoulos, "Lyapunov-driven deep reinforcement learning for edge inference empowered by reconfigurable intelligent surfaces," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Rhodes, Greece, 4–9 June 2023, pp. 1–5. C119. J. He, A. Fakhreddine, H. Wymeersch, and G. C. Alexandropoulos, "Compressed-sensing-based 3D localization with distributed passive reconfigurable intelligent surfaces," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Rhodes, Greece, 4–9 June 2023, pp. 1–5. C118. J. He, A. Fakhreddine, and G. C. Alexandropoulos, "Joint channel and direction estimation for ground-to-UAV communications enabled by a simultaneous reflecting and sensing RIS," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Rhodes, Greece, 4–9 June 2023, pp. 1–5. C117. S. Ghose, D. Mishra, S. P. Maity, and G. C. Alexandropoulos, "RIS reflection and placement optimization for underlay D2D communications in cognitive cellular networks," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Rhodes, Greece, 4–9 June 2023, pp. 1–5. C116. D. Kompostiotis, D. Vordonis, V. Paliouras, and G. C. Alexandropoulos, "Secrecy rate maximization in RIS-enabled OFDM wireless communications: The circuit-based reflection model case," in Proc. IEEE International Conference on Communications, Rome, Italy, 28 May–1 June 2023, pp. 1–6. C115. L. Wei, C. Huang, G. C. Alexandropoulos, Z. Yang, J. Yang, C. Yuen, and M. Debbah, "Channel modeling and multi-user precoding for tri-polarized holographic MIMO communications," in Proc. IEEE International Conference on Communications, Rome, Italy, 28 May–1 June 2023, pp. 1–6. C114. H. Kim, A. Fascista, H. Chen, Y. Ge, G. C. Alexandropoulos, G. Seco-Granados, and H. Wymeersch, "RIS–aided radar sensing and object detection with single and double bounce multipath," in Proc. IEEE International Conference on Communications, Rome, Italy, 28 May–1 June 2023, pp. 1–6. C113. A. Mondal, D. Mishra, G. Prasad, G. C. Alexandropoulos, and A. Hossain, "Reinforcement-learning-based UAV utility maximization for offloading cellular communication systems," in Proc. IEEE International Conference on Communications, Rome, Italy, 28 May–1 June 2023, pp. 1–6. C112. R. Ghazalian, H. Chen, G. C. Alexandropoulos, G. Seco-Granados, H. Wymeersch, and R. Jäntti, "RIS position and orientation estimation via multi-carrier transmissions and multiple receivers," in Proc. IEEE International Conference on Communications, Rome, Italy, 28 May–1 June 2023, pp. 1–6. C111. I. Alamzadeh, N. Shlezinger, G. C. Alexandropoulos, and M. F. Imani, "Hybrid reconfigurable intelligent surfaces with sensing and reconfigurable reflection capabilities," in Proc. URSI International Symposium on Electromagnetic Theory, Vancouver, Canada, 22–26 May 2023. C110. R. Faqiri, C. Saigre-Tardif, G. C. Alexandropoulos, N. Shlezinger, M. F. Imani, and P. del Hougne, "PhysFad: Physics-based end-to-end communication modeling of generic programmable-metasurface-parametrized radio environments of arbitrary complexity," in Proc. URSI International Symposium on Electromagnetic Theory, Vancouver, Canada, 22–26 May 2023. C109. Q. Luo, G. C. Alexandropoulos, Y. Zhou, and X. Ma, "Ultra-wideband metasurface at SubTHz: Hardware design and reflection optimization," in Proc. European Conference on Antennas and Propagation, Florence, Italy, 26–29 March 2023, pp. 1–5. C108. Z. Abdullah, G. C. Alexandropoulos, S. Kisseleff, S. Chatzinotas, and B. Ottersten, "Combining relaying and reflective surfaces: Power consumption and energy efficiency analysis," in Proc. IEEE Global Communications Conference, Rio de Janeiro, Brazil, 4–8 December 2022, pp. 1–6. C107. R. Faqiri, C. Saigre-Tardif, G. C. Alexandropoulos, N. Shlezinger, M. F. Imani, and P. del Hougne, "A physics-based fading channel model for smart wireless environments enabled by reconfigurable intelligent surfaces," in Proc. IEEE Global Communications Conference, Rio de Janeiro, Brazil, 4–8 December 2022, pp. 1–6. C106. M. A. Islam, G. C. Alexandropoulos, and B. Smida, "Simultaneous multi-user MIMO communications and multi-target tracking with full duplex radios," in Proc. IEEE Global Communications Conference, Rio de Janeiro, Brazil, 4–8 December 2022, pp. 1–6. C105. K. Chen-Hu, G. C. Alexandropoulos, and A. García Armada, "Simultaneous RIS tuning and differential data transmission for MISO OFDM wireless systems," in Proc. IEEE Global Communications Conference, Rio de Janeiro, Brazil, 4–8 December 2022, pp. 1–6. C104. M. Merluzzi, F. Costanzo, K. D. Katsanos, G. C. Alexandropoulos, and P. Di Lorenzo, "Power minimizing MEC offloading with probabilistic QoS constraints for RIS-empowered communication systems," in Proc. IEEE Global Communications Conference, Rio de Janeiro, Brazil, 4–8 December 2022, pp. 1–6. C103. K. D. Katsanos and G. C. Alexandropoulos, "Safeguarding MIMO communications with reconfigurable metasurfaces and artificial noise," in Proc. 6G Summit, Abu Dhabi, UAE, 3–4 November 2022. C102. J. He, A. Fakhreddine, and G. C. Alexandropoulos, "Simultaneous indoor and outdoor 3D localization with STAR-RIS-assisted millimeter wave systems," in Proc. 6G Summit, Abu Dhabi, UAE, 3–4 November 2022. C101. K. D. Katsanos and G. C. Alexandropoulos, "Secrecy spectral efficiency optimization in RIS-enabled MIMO communication systems," in Proc. IEEE International Conference on Very Large Scale Integration, Patras, Greece, 3–5 October 2022, pp. 1–6. C100. J. He, A. Fakhreddine, and G. C. Alexandropoulos, "Simultaneous indoor and outdoor 3D localization with STAR-RIS-assisted millimeter wave systems," in Proc. IEEE Vehicular Technology Conference, London/Beijing, UK/China, 26–29 September 2022, pp. 1–6. C99. R. Faqiri, C. Saigre-Tardif, G. C. Alexandropoulos, N. Shlezinger, M. F. Imani, and P. del Hougne, "PhysFad: Physics-based end-to-end communication modeling of programmable-metasurface-parametrized environments with adjustable fading," in Proc. International Congress on Artificial Materials for Novel Wave Phenomena, Siena, Italy, 12–17 September 2022, pp. 1–6. C98. R. Liu, G. C. Alexandropoulos, Q. Wu, M. Jian, and Y. Liu, "How can reconfigurable intelligent surfaces drive 5G-advanced wireless networks: A standardization perspective," in Proc. IEEE/CIC International Conference on Communications in China, Foshan, China, 11–13 August 2022, pp. 1–6. C97. K. Stylianopoulos and G. C. Alexandropoulos, "Online RIS configuration learning for arbitrary large numbers of 1-bit phase resolution elements," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Oulu, Finland, 4–6 July 2022, pp. 1–6. C96. K. D. Katsanos, P. Di Lorenzo, and G. C. Alexandropoulos, "Distributed sum-rate maximization of cellular communications with multiple reconfigurable intelligent surfaces," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Oulu, Finland, 4–6 July 2022, pp. 1–6. C95. G. C. Alexandropoulos, V. Jamali, R. Schober, and H. V. Poor, "Near-field channel estimation for RIS-enabled millimeter wave MIMO communication systems," IEEE Sensor Array and Multichannel Signal Processing Workshop, Trondheim, Norway, 20–23 June 2022, pp. 1–5. C94. G. C. Alexandropoulos, M. Crozzoli, D.-T. Phan-Huy, K. D. Katsanos, H. Wymeersch, P. Popovski, P. Ratajczak, Y. Bénédic, M.-H. Hamon, S. Herraiz Gonzalez, R. D'Errico, and E. Calvanese Strinati, "Smart wireless environments enabled by RISs: Deployment scenarios and two key challenges," in Proc. Joint European Conference on Networks and Communications & 6G Summit, Grenoble, France, 7–10 June 2022, pp. 1–6. C93. Q. Li, M. Wen, E. Basar, G. C. Alexandropoulos, K. J. Kim, and H. V. Poor, "Cyclic-prefixed single-carrier transmission with reconfigurable intelligent surfaces," in Proc. Joint European Conference on Networks and Communications & 6G Summit, Grenoble, France, 7–10 June 2022, pp. 1–6. C92. L. Wei, C. Huang, G. C. Alexandropoulos, W. E. I. Sha, Z. Zhang, M. Debbah, and C. Yuen, "Multi-user wireless communications with holographic MIMO surfaces: A convenient channel model and spectral efficiency analysis," in Proc. Joint European Conference on Networks and Communications & 6G Summit, Grenoble, France, 7–10 June 2022, pp. 1–6. C91. M. Rahal, B. Denis, K. Keykhosravi, M. F. Keskin, B. Uguen, G. C. Alexandropoulos, and H. Wymeersch, "Arbitrary beam pattern approximation via RISs with measured element responses," in Proc. Joint European Conference on Networks and Communications & 6G Summit, Grenoble, France, 7–10 June 2022, pp. 1–6. C90. A. Mokh, J. de Rosny, G. C. Alexandropoulos, M. Kamoun, A. Ourir, R. Khayatzadeh, A. Tourin, and M. Fink, "Experimental validation of time reversal multiple access for UWB wireless communications centered at the 273.6 GHz frequency," in Proc. IEEE Vehicular Technology Conference Spring, Helsinki, Finland, 19–22 June 2022, pp. 1–5. C89. M. A. Islam, G. C. Alexandropoulos, and B. Smida, "Integrated sensing and communication with millimeter wave full duplex hybrid beamforming," in Proc. IEEE International Conference on Communications, Seoul, South Korea, 16–20 May 2022, pp. 1–6. C88. K. Stylianopoulos, G. C. Alexandropoulos, C. Huang, C. Yuen, M. Bennis, and M. Debbah, "Deep contextual bandits for orchestrating multi-user MISO systems with multiple RISs," in Proc. IEEE International Conference on Communications, Seoul, South Korea, 16–20 May 2022, pp. 1–6. C87. K. D. Katsanos, N. Shlezinger, M. F. Imani, and G. C. Alexandropoulos, "Wideband multi-user MIMO communications with frequency selective RISs: Element response modeling and sum-rate maximization," in Proc. IEEE International Conference on Communications, Seoul, South Korea, 16–20 May 2022, pp. 1–6. C86. K. Keykhosravi, G. Seco-Granados, G. C. Alexandropoulos, and H. Wymeersch, "RIS-enabled self-localization: Leveraging controllable reflections with zero access points," in Proc. IEEE International Conference on Communications, Seoul, South Korea, 16–20 May 2022, pp. 1–6. C85. J. Yuan, G. C. Alexandropoulos, E. Kofidis, T. L. Jensen, and E. De Carvalho, "Channel tracking for RIS-enabled multi-user SIMO systems in time-varying wireless channels," in Proc. IEEE International Conference on Communications, Seoul, South Korea, 16–20 May 2022, pp. 1–6. C84. K. Stylianopoulos, N. Shlezinger, P. del Hougne, and G. C. Alexandropoulos, "Deep-learning-assisted configuration of reconfigurable intelligent surfaces in dynamic rich-scattering environments," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Singapore, 22–27 May 2022, pp. 1–5. C83. V. Kouni, G. Paraskevopoulos, H. Rauhut, and G. C. Alexandropoulos, "ADMM-DAD Net: A deep unfolding network for analysis compressed sensing," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Singapore, 22–27 May 2022, pp. 1–5. C82. A. Mokh, J. de Rosny, G. C. Alexandropoulos, R. Khayatzadeh, M. Kamoun, A. Ourir, A. Tourin, and M. Fink, "Time reversal for multiple access and mobility: Algorithmic design and experimental results," in Proc. IEEE Wireless Communications and Networking Conference, Austin, USA, 10–13 April 2022, pp. 1–6. C81. K. Chen-Hu, G. C. Alexandropoulos, and A. García Armada, "Non-Coherent MIMO-OFDM uplink empowered by the spatial Diversity in reflecting surfaces," in Proc. IEEE Wireless Communications and Networking Conference, Austin, USA, 10–13 April 2022, pp. 1–6. C80. I. Alamzadeh, G. C. Alexandropoulos, N. Shlezinger, and M. F. Imani, "A hybrid intelligent surface with simultaneous sensing and reconfigurable reflection capability," in Proc. USNC-URSI National Radio Science Meeting, virtual, 4–8 January 2022, pp. 1–6. C79. A. Mokh, J. de Rosny, G. C. Alexandropoulos, R. Khayatzadeh, A. Ourir, M. Kamoun, A. Tourin, and M. Fink, "Time reversal precoding at subTHz frequencies: Experimental results on spatiotemporal focusing," in Proc. IEEE Conference on Standards for Communications and Networking, Virtual Conference, 15–17 December 2021, pp. 1–6. C78. A. L. Moustakas, G. C. Alexandropoulos, and M. Debbah, "Capacity optimization using reconfigurable intelligent surfaces: A large system approach," in Proc. IEEE Global Communications Conference, Madrid, Spain, 7–11 December 2021, pp. 1–6. C77. M. A. Islam, G. C. Alexandropoulos, and B. Smida, "Direction-assisted beam management in full duplex millimeter wave massive MIMO systems," in Proc. IEEE Global Communications Conference, Madrid, Spain, 7–11 December 2021, pp. 1–6. (Best Paper Award 2021 for the Selected Areas in Communications Symposium) C76. J. Xu, L. You, G. C. Alexandropoulos, J. Wang, W. Wang, and X. Gao, "Dynamic metasurface antennas for energy efficient uplink massive MIMO communications," in Proc. IEEE Global Communications Conference, Madrid, Spain, 7–11 December 2021, pp. 1–6. C75. I. Alamzadeh, M. F. Imani, G. C. Alexandropoulos, and N. Shlezinger, "A reconfigurable reflecting metasurface with sensing capabilities," in Proc. IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, Marina Bay Sands, Singapore, 4–10 December 2021. C74. L. Wang, N. Shlezinger, G. C. Alexandropoulos, H. Zhang, B. Wang, and Y. C. Eldar, "Jointly learned symbol detection and signal reflection in RIS-empowered multi-user MISO communication systems," in Proc. IEEE Asilomar Signals, Systems and Computer Conference, Pacific Grove, USA, 31 October–3 November 2021, pp. 1–7. C73. H. Zhang, N. Shlezinger, I. Alamzadeh, G. C. Alexandropoulos, M. F. Imani, and Y. C. Eldar, "Channel estimation with simultaneous reflecting and sensing reconfigurable intelligent metasurfaces," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Lucca, Italy, 27–30 September 2021, pp. 1–6. C72. E. Calvanese Strinati, G. C. Alexandropoulos, V. Sciancalepore, M. Di Renzo, H. Wymeersch, D.-T. Phan-Huy, M. Crozzoli, R. D'Errico, E. De Carvalho, P. Popovski, P. Di Lorenzo, L. Bastianelli, M. Belouar, J. E. Mascolo, G. Gradoni, S. Phang, G. Lerosey, and B. Denis, "Wireless environment as a service enabled by reconfigurable intelligent surfaces: The RISE-6G perspective," in Proc. Joint European Conference on Networks and Communications & 6G Summit, Porto, Portugal, 8–11 June 2021, pp. 1–6. C71. G. C. Alexandropoulos, K. Katsanos, M. Wen, and D. B. da Costa, "Safeguarding MIMO communications with reconfigurable metasurfaces and artificial noise," in Proc. IEEE International Conference on Communications, Montreal, Canada, 14–18 June 2021, pp. 1–6. C70. Z. Abu-Shaban, K. Keykhosravi, M. F. Keskin, G. C. Alexandropoulos, G. Seco-Granados, and H. Wymeersch, "Near-field localization with a reconfigurable intelligent surface acting as lens," in Proc. IEEE International Conference on Communications, Montreal, Canada, 14–18 June 2021, pp. 1–6. C69. C. Xiang, S. Zhang, S. Xu, and G. C. Alexandropoulos, "Self-calibrating indoor localization with crowdsourcing fingerprints and transfer learning," in Proc. IEEE International Conference on Communications, Montreal, Canada, 14–18 June 2021, pp. 1–6. C68. G. C. Alexandropoulos, I. Vinieratou, M. Rebato, L. Rose, and M. Zorzi, "Uplink beam management for millimeter wave cellular MIMO systems with hybrid beamforming," in Proc. IEEE Wireless Communications and Networking Conference, Nanjing, China, 29 March–1 April 2021, pp. 1–7. C67. L. Wei, C. Huang, G. C. Alexandropoulos, Z. Yang, C. Yuen, and Z. Zhang, "Joint channel estimation and signal recovery in RIS-assisted multi-user MISO communications," in Proc. IEEE Wireless Communications and Networking Conference, Nanjing, China, 29 March–1 April 2021, pp. 1–6. C66. G. C. Alexandropoulos, S. Samarakoon, M. Bennis, and M. Debbah, "Phase configuration learning in wireless networks with multiple reconfigurable intelligent surfaces," in Proc. IEEE Global Communications Conference, Taipei, Taiwan, 7–11 December 2020, pp. 1–6. C65. C. Huang, Z. Yang, G. C. Alexandropoulos, K. Xiong, L. Wei, C. Yuen, and Z. Zhang, "Hybrid beamforming for RIS-empowered multi-hop terahertz communications: A DRL-based method," in Proc. IEEE Global Communications Conference, Taipei, Taiwan, 7–11 December 2020, pp. 1–6. C64. S. Lin, B. Zheng, G. C. Alexandropoulos, M. Wen, M. Di Renzo, and F. Chen, "Joint passive beamforming and information transfer for RIS-empowered wireless communications," in Proc. IEEE Global Communications Conference, Taipei, Taiwan, 7–11 December 2020, pp. 1–6. C63. S. Lin, B. Zheng, G. C. Alexandropoulos, M. Wen, F.-J. Chen, and S. Mumtaz, "Progressive channel estimation and passive beamforming for RIS-assisted OFDM systems," in Proc. IEEE Global Communications Conference, Taipei, Taiwan, 7–11 December 2020, pp. 1–6. C62. G. C. Alexandropoulos, E. Vlachos, and B. Smida, "Localization and channel estimation for UAV-assisted millimeter wave communications," in Proc. IEEE Asilomar Signals, Systems and Computer Conference, Pacific Grove, USA, 1–5 November 2020, pp. 1–5. C61. M. A. Islam, G. C. Alexandropoulos, and B. Smida, "Simultaneous data communication and channel estimation in multiuser full duplex MIMO systems," in Proc. IEEE Asilomar Signals, Systems and Computer Conference, Pacific Grove, USA, 1–5 November 2020, pp. 1–5. C60. G. C. Alexandropoulos, M. A. Islam, and B. Smida, "Full duplex hybrid A/D beamforming with reduced complexity multi-tap analog cancellation," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Atlanta, USA, 26–29 May 2020, pp. 1–6. C59. S. Zhu, Y. Peng, G. C. Alexandropoulos, K. Li, "RCS-based flight target recognition using deep networks with convolutional and bidirectional GRU layers," in Proc. International Conference on Innovation in Artificial Intelligence, Xiamen, China, 6–9 March 2020, pp. 1–6. C58. L. Wei, C. Huang, G. C. Alexandropoulos, and C. Yuen, "Parallel factor decomposition channel estimation in RIS-assisted multi-user MISO communication," in Proc. IEEE Sensor Array and Multichannel Signal Processing Workshop, Hangzhou, China, 8–11 June 2020, pp. 1–6. C57. M. A. Islam, G. C. Alexandropoulos, and B. Smida, "Simultaneous downlink data transmission and uplink channel estimation with reduced complexity full duplex MIMO radios," in Proc. IEEE International Conference on Communications, Dublin, Ireland, 7–11 June 2020, pp. 1–6. C56. M. Duarte and G. C. Alexandropoulos, "Full duplex MIMO digital beamforming with reduced complexity AUXTX analog cancellation," in Proc. IEEE International Conference on Communications, Dublin, Ireland, 7–11 June 2020, pp. 1–6. C55. G. C. Alexandropoulos and E. Vlachos, "A hardware architecture for reconfigurable intelligent surfaces with minimal active elements for explicit channel estimation," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Barcelona, Spain, 4–8 May 2020, pp. 9175–9179. C54. G. C. Alexandropoulos, E. Vlachos, and J. Thompson, "Wideband channel tracking for millimeter wave massive MIMO systems with hybrid beamforming reception," in Proc. International Conference on Acoustics, Speech, and Signal Processing, Barcelona, Spain, 4–8 May 2020, pp. 8698–8702. C53. A. L. Moustakas, G. C. Alexandropoulos, A. Polydoros, I. Kaddas, and I. Dagres, "Impact of imperfect channel estimation in HF OFDM-MIMO communications," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Istanbul, Turkey, 8–11 September 2019, pp. 1–6. C52. M. A. Islam, G. C. Alexandropoulos, and B. Smida, "A unified beamforming and A/D self-interference cancellation design for full duplex MIMO radios," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Istanbul, Turkey, 8–11 September 2019, pp. 1–6. C51. M. A. B. Abbasi, H. Tataria, V. F. Fusco, M. Matthaiou, and G. C. Alexandropoulos, "Aggressive RF circuit reduction techniques in millimeter wave cellular systems," in Proc. IEEE International Symposium on Wireless Communication Systems, Oulu, Finland, 27–30 August 2019, pp. 1–6. C50. E. Vlachos, G. C. Alexandropoulos, and J. Thompson, "Hybrid beamforming with random analog sampling for wideband channel estimation in millimeter wave massive MIMO systems," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Cannes, France, 2–5 July 2019, pp. 1–6. C49. C. Huang, G. C. Alexandropoulos, C. Yuen, and M. Debbah, "Indoor signal focusing with deep learning designed reconfigurable intelligent surfaces," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Cannes, France, 2–5 July 2019, pp. 1–6. C48. E. Vlachos, G. C. Alexandropoulos, and J. Thompson, "Wideband MIMO channel estimation for hybrid beamforming millimeter wave systems via random spatial sampling," IEEE Communication Theory Workshop, Selfoss, Iceland, 26–29 May 2019. C47. C. Huang, G. C. Alexandropoulos, A. Zappone, C. Yuen, and M. Debbah, "Deep learning for UL/DL channel calibration in generic massive MIMO systems," in Proc. IEEE International Conference on Communications, Shanghai, China, 20–24 May 2019, pp. 1–6. C46. G. C. Alexandropoulos, R. Khayatzadeh, M. Kamoun, Y. Ganghua, and M. Debbah, "Indoor time reversal wireless communication: Experimental results for localization and signal coverage," in Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, Brighton, UK, 12–17 May 2019, pp. 1–5. C45. H. Iimori, G. Abreu, K. Ishibashi, and G. C. Alexandropoulos, "Transmission strategies in imperfect bi-directional full-duplex MIMO systems," in Proc. IEEE Wireless Communications and Networking Conference, Marrakech, Morocco, 15–18 April 2019, pp. 1–6. C44. C. Huang, G. C. Alexandropoulos, A. Zappone, M. Debbah, and C. Yuen, "Energy efficient multi-user MISO communication using low resolution large intelligent surfaces," in Proc. IEEE Global Communications Conference, Abu Dhabi, UAE, 9–13 December 2018, pp. 1–6. C43. H. Iimori, G. Abreu, and G. C. Alexandropoulos, "Full-duplex transmission optimization for bi-directional MIMO links with QoS guarantees," in Proc. IEEE Global Conference on Signal and Information Processing, Anaheim, USA, 26–28 November 2018, pp. 1–6. C42. E. Vlachos, G. C. Alexandropoulos, and J. Thompson, "ADMM-based wideband channel estimation for millimeter wave MIMO communications," in Proc. International Workshop on Millimeter Wave Radio Communication Technologies, Queen's University Belfast, UK, 15 November 2018. C41. H. Iimori, G. Abreu, and G. C. Alexandropoulos, "Full-duplex bi-directional MIMO under imperfect CSI and hardware impairments," in Proc. IEEE Workshop on Positioning, Navigation, and Communications, Bremen, Germany, 25–26 October 2018, pp. 1–6. C40. H. Tataria, M. Matthaiou, P. J. Smith, G. C. Alexandropoulos, and V. F. Fusco, "Impact of RF processing and switching errors in lens-based massive MIMO systems," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Kalamata, Greece, 25–28 June 2018, pp. 1–5. C39. N. I. Miridakis, T. A. Tsiftsis, and G. C. Alexandropoulos, "Energy efficient transmission in underlay massive MIMO systems with probabilistic guarantees," in Proc. IEEE International Conference on Communications, Kansas City, USA, 20–24 May 2018, pp. 1–5. C38. D. Mishra, G. C. Alexandropoulos, and S. De, "Harvested power fairness optimization in MISO SWIPT multicasting IoT with individual constraints," in Proc. IEEE International Conference on Communications, Kansas City, USA, 20–24 May 2018, pp. 1–5. C37. H. Tataria, M. Matthaiou, P. J. Smith, G. C. Alexandropoulos, and V. F. Fusco, "Uplink interference analysis with RF switching for lens-based millimeter-wave systems," in Proc. IEEE International Conference on Communications, Kansas City, USA, 20–24 May 2018, pp. 1–6. C36. G. C. Alexandropoulos, "Position aided beam alignment for millimeter wave backhaul systems with large phased arrays," in Proc. IEEE Workshop on Computational Advances in Multi-Sensor Adaptive Processing, Curaçao, Dutch Antilles, 10–13 December 2017, pp. 1–5. C35. D. Mishra and G. C. Alexandropoulos, "Harvested power maximization in QoS-constrained MIMO SWIPT with generic RF harvesting model," in Proc. IEEE Workshop on Computational Advances in Multi-Sensor Adaptive Processing, Curaçao, Dutch Antilles, 10–13 December 2017, pp. 1–5. C34. D. Mishra, S. De, G. C. Alexandropoulos, and D. Krishnaswamy, "Energy-aware mode selection for throughput maximization in RF-powered D2D communications," in Proc. IEEE Global Communications Conference, Singapore, 4–8 December 2017, pp. 1–6. C33. G. C. Alexandropoulos and M. Duarte, "Joint design of multi-tap analog cancellation and digital beamforming for reduced complexity full duplex MIMO systems," in Proc. IEEE International Conference on Communications, Paris, France, 21–25 May 2017, pp. 1–7. C32. S. Vassilaras and G. C. Alexandropoulos, "Cooperative beamforming techniques for energy efficient IoT wireless communication," in Proc. IEEE International Conference on Communications, Paris, France, 21–25 May 2017, pp. 1–6. C31. G. C. Alexandropoulos, P. Ferrand, and C. B. Papadias, "On the robustness of coordinated beamforming to uncoordinated interference and CSI uncertainty," in Proc. IEEE Wireless Communications and Networking Conference, San Francisco, USA, 19–22 March 2017, pp. 1–6. C30. G. C. Alexandropoulos and S. Chouvardas, "Low complexity channel estimation for millimeter wave systems with hybrid A/D antenna processing," in Proc. IEEE Global Communications Conference, Washington D.C., USA, 4–8 December 2016, pp. 1–6. C29. N. I. Miridakis, T. A. Tsiftsis, G. C. Alexandropoulos, and M. Debbah, "Simultaneous spectrum sensing and data transmission for multi-user MIMO cognitive radio systems," in Proc. IEEE Global Communications Conference, Washington D.C., USA, 4–8 December 2016, pp. 1–6. C28. G. C. Alexandropoulos, P. T. Mathiopoulos, and P. Fan, "Multibranch scan-and-wait combining receivers over correlated Nakagami-m fading channels," in Proc. IEEE International Conference on Signal Processing, Chengdu, China, 6–10 November 2016, pp. 1236–1241. C27. G. C. Alexandropoulos, M. Kountouris, and I. Atzeni, "User scheduling and optimal power allocation for full-duplex cellular networks," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Edinburgh, UK, 3–6 July 2016, pp. 1–6. C26. S. Vassilaras and G. C. Alexandropoulos, "Optimizing access mechanisms for QoS provisioning in hardware constrained dynamic spectrum access," in Proc. IEEE International Workshop on Signal Processing Advances in Wireless Communications, Edinburgh, UK, 3–6 July 2016, pp. 1–6. C25. M. Fozooni, M. Matthaiou, S. Jin, and G. C. Alexandropoulos, "Massive MIMO relaying with hybrid processing," in Proc. IEEE International Conference on Communications, Kuala Lumpur, Malaysia, 23–27 May 2016, pp. 1–6. C24. N. I. Miridakis, T. A. Tsiftsis, G. C. Alexandropoulos, and M. Debbah, "Energy efficient switching between data transmission and energy harvesting for cooperative cognitive relaying systems," in Proc. IEEE International Conference on Communications, Kuala Lumpur, Malaysia, 23–27 May 2016, pp. 1–6. C23. I. Atzeni, M. Kountouris, and G. C. Alexandropoulos, "Performance evaluation of user scheduling for full-duplex small cells in ultra-dense networks," in Proc. European Wireless Conference, Oulu, Finland, 18–20 May 2016, pp. 1–6. C22. Y. Liu, G. C. Alexandropoulos, L. Li, and M. Pesavento, "Artificial noise design for secure multi-relay networks over generalized fading channels," in Proc. International Conference on TeleCommunications, Thessaloniki, Greece, 16–18 May 2016, pp. 492–496. C21. G. C. Alexandropoulos and M. Kountouris, "Maximal ratio transmission in wireless Poisson networks under spatially correlated fading channels," in Proc. IEEE Global Communications Conference, San Diego, USA, 6–10 December 2015, pp. 1–6. C20. S. Vassilaras, G. C. Alexandropoulos, and A. A. Kalis, "Bit error rate analysis of cooperative beamforming for transmitting individual data streams," in Proc. IEEE International Conference on Communications, London, UK, 8–12 June 2015, pp. 7856–7861. C19. G. C. Alexandropoulos, V. I. Barousis, and C. B. Papadias, "Precoding for multiuser MIMO systems with single-fed parasitic antenna arrays," in Proc. IEEE Global Communications Conference, Austin, USA, 8–12 December 2014, pp. 3656–3661. C18. Y. Peng, G. C. Alexandropoulos, P. Wang, Y. Li, and D.-B. Ha, "Secret key generation for OFDM TDD systems over frequency selective fading channels," in Proc. International Conference on Communications and Networking in China, Maoming, China, 14–16 August 2014, pp. 1–2. C17. N. Taramas, G. C. Alexandropoulos, and C. B. Papadias, "Opportunistic beamforming for secondary users in licensed shared access networks," in Proc. IEEE International Symposium on Communications, Control and Signal Processing, Athens, Greece, 21–23 May 2014, pp. 567–570. C16. G. C. Alexandropoulos, S. Papaharalabos, and C. B. Papadias, "On the performance of transceiver techniques for the K-User MIMO IFC with LTE-A turbo coding," in Proc. IEEE Wireless Communications and Networking Conference, Istanbul, Turkey, 6 April 2014, pp. 271–275. C15. G. C. Alexandropoulos and C. B. Papadias, "A reconfigurable distributed algorithm for K-user MIMO interference networks," in Proc. IEEE International Conference on Communications, Budapest, Hungary, 9–13 June 2013, pp. 1656–1660. C14. S. Papaharalabos, G. C. Alexandropoulos, and C. B. Papadias, "A comparative study of interference alignment schemes with LTE-compliant turbo coding," in Proc. IEEE International Conference on Communications, Budapest, Hungary, 9 June 2013, pp. 159–163. C13. Y. Peng, G. C. Alexandropoulos, H. Zhao, and H. Duan, "Performance analysis of OMP-based channel estimation for OFDM systems with periodical pilots and virtual subcarriers," in Proc. International Conference on Computing, Management and Telecommunications, Ho Chi Minh City, Vietnam, 21–24 January 2013, pp. 11–16. C12. M. Matthaiou, G. C. Alexandropoulos, H. Q. Ngo, and E. G. Larsson, "Effective rate analysis of MISO Ricean fading channels," in Proc. IEEE Sensor Array and Multichannel Signal Processing Workshop, New Jersey, USA, 17–20 June 2012, pp. 53–56. C11. G. C. Alexandropoulos, S. Papaharalabos, and C. B. Papadias, "On the performance of interference alignment under weak interference conditions," in Proc. IEEE International Conference on Systems, Signals and Image Processing, Vienna, Austria, 11–13 April 2012, pp. 232–236. C10. G. C. Alexandropoulos, A. Conti, and P. T. Mathiopoulos, "Adaptive M-QAM systems with diversity in correlated Nakagami-m fading and shadowing," in Proc. IEEE Global Communications Conference, Florida, USA, 6–10 December 2010, pp. 1–5. C9. G. C. Alexandropoulos, A. Papadogiannis, and K. Berberidis, "Relay selection vs. repetitive transmission cooperation: analysis under Nakagami-m fading," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Istanbul, Turkey, 26–29 September 2010, pp. 140–144. C8. A. Papadogiannis and G. C. Alexandropoulos, "The value of dynamic clustering of base stations for the wireless networks of the future," in Proc. IEEE World Congress on Computational Intelligence, Barcelona, Spain, 18–23 July 2010, pp. 1–6. C7. L. Jacobs, G. C. Alexandropoulos, M. Moeneclaey, and P. T. Mathiopoulos, "BER performance of OSTBCs on correlated fading channels with imperfect channel estimation," in Proc. Future Network and Mobile Summit Conference, Florence, Italy, 16–18 June 2010, pp. 1–8. C6. A. Papadogiannis and G. C. Alexandropoulos, "System level performance evaluation of dynamic relays in cellular networks over Nakagami-m fading channels," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Tokyo, Japan, 13–16 September 2009, pp. 727–731. C5. L. Jacobs, G. C. Alexandropoulos, M. Moeneclaey, and P. T. Mathiopoulos, "BER of MRC for M-QAM with imperfect channel estimation over correlated Nakagami-m Fading," in Proc. Newcom++/ACoRN Joint Workshop, Barcelona, Spain, 30 March–1 April 2009, pp. 1–5. C4. G. C. Alexandropoulos, N. C. Sagias, F. I. Lazarakis, and K. Berberidis, "New results on SC and MRC over Nakagami-m fading channels with arbitrary correlation matrix," in Proc. IEEE Global Communications Conference, Washington D.C., USA, 26–30 November 2007, pp. 1551–1555. C3. G. C. Alexandropoulos, K. Berberidis, N. C. Sagias, F. I. Lazarakis, A. A. Alexandridis, and K. Dangakis, "Householder-matrices based analysis of SC receivers over Rayleigh fading channels with arbitrary correlation," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Athens, Greece, 3–7 September 2007, pp. 1–5. C2. G. C. Alexandropoulos, K. Berberidis, N. C. Sagias, F. I. Lazarakis, C. K. Datsikas, A. A.  Alexandridis, and K. Dangakis, "On the sum of squared Rayleigh variates and applications to maximal-ratio diversity," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Athens, Greece, 3–7 September 2007, pp. 1–5. C1. C. K. Datsikas, G. S. Tombras, N. C. Sagias, F. I. Lazarakis, G. C. Alexandropoulos, A. A. Alexandridis, and K. Dangakis, "Dual-hop relaying networks over Nakagami-m fading channels," in Proc. IEEE International Symposium on Personal, Indoor, and Mobile Radio Communications, Athens, Greece, 3–7 September 2007, pp. 1–4.   Books B1. G. C. Alexandropoulos, A. Zappone, N. Shlezinger, M. Di Renzo, and Y. C. Eldar, "Reconfigurable Metasurfaces for Wireless Communications: Architectures, Modeling, and Optimization," Springer Nature, Singapore, to appear, 2025.   Book Chapters BC5. M. Delbari, G. C. Alexandropoulos, R. Schober, and V. Jamali, "Far- versus near-field RIS modeling and beam design,” in the book “Reconfigurable Metasurfaces for Wireless Communications: Architectures, Modeling, and Optimization," Springer Nature, Singapore, to appear, 2025. BC4. I. Gavras and G. C. Alexandropoulos, "Full duplex massive MIMO for integrated sensing and communications,” in the book “Integrated Sensing and Communications for Future Wireless Networks: Principles, Advances, and Key Enabling Technologies," Elsevier Inc., Amsterdam, to appear, 2024. BC3. E. Vlachos, A. Kaushik, and G. C. Alexandropoulos, “Flexible hybrid precoding for integrated sensing and communications,” in the book "Integrated Sensing and Communications for Future Wireless Networks: Principles, Advances, and Key Enabling Technologies," Elsevier Inc., Amsterdam, to appear, 2024. BC2. G. C. Alexandropoulos, H. Kim, J. He, and H. Wymeersch, "Localization, sensing, and their integration with RISs," in the book "Intelligent Reflecting Surface Empowered 6G Network," John Wiley & Sons, Inc., Hoboken, New Jersey, 2023. BC1. R. Liu, K. D. Katsanos, Q. Wu, and G. C. Alexandropoulos, "Overview of IRS for 6G and industry advance," in the book "Intelligent Reflecting Surface Empowered 6G Network," John Wiley & Sons, Inc., Hoboken", New Jersey, 2023.   Patents P4. B. Smida, M. A. Islam, and G. C. Alexandropoulos, "Integrated sensing and communication with millimeter wave full duplex hybrid beamforming," filed (UIC 2023-006-01) 10 September, 2022. P3. A. Fakhreddine, C.–F. Bader, G. C. Alexandropoulos, and M. Debbah, "Reconfigurable intelligent surfaces for three-dimensional cellular coverage," filed (PCT/GR2022/000045) 2 September, 2022. P2. G. C. Alexandropoulos and M. Duarte, "A full-duplex wireless beamforming apparatus with self-interference cancellation and method," filed (PCT/EP2016/073257) 29 September, 2016; granted (WO2018059691A1) 5 April, 2018; available online. P1. G. C. Alexandropoulos, "A communication apparatus and a method of operating a communication apparatus," filed (PCT/EP2015/074384) 21 October, 2015; granted (WO2017067591A1) 27 April, 2017; available online.   Project Deliverables D59.TERRAMETA Deliverable D3.2, "Report on THz components design (interim)," December 2023. D58. TERRAMETA Deliverable D7.2, "Report on Dissemination Standardisation and Exploitation Activities (initial)," December 2023. D57. RISE-6G Deliverable D8.4, "Final report on exploitation of knowledge and results," December 2023. D56. RISE-6G Deliverable D8.5, "Final dissemination and standardization activity report," December 2023. D55. RISE-6G Deliverable D7.3, "Final results of PoCs and trials," December 2023. D54. RISE-6G Deliverable D3.4, "Optimized RIS prototypes for PoCs and model assessment," December 2023. D53. RISE-6G Deliverable D2.6, "RISE network architectures and deployment strategies analysis: final results," December 2023. D52. RISE-6G Deliverable D1.3, "Final project management report," December 2023. D51. PRISM Deliverable D1, "Emerging applications served by RIS localization and mapping," October 2023. D50. RISE-6G Deliverable D6.4, "Sustainable RIS solutions design for EE, EMFEU and SSE (Final Specifications)," September 2023. D49. RISE-6G Deliverable D5.4, "Estimation algorithms for RIS-based localisation, mapping and sensing (Final Specifications)," September 2023. D48. RISE-6G Deliverable D4.4, "Multi-user techniques and connectivity of RIS based communication and mobile edge computing (Final Specifications)," September 2023. D47. TERRAMETA Deliverable D8.6, "Data management plan," June 2023. D46. TERRAMETA Deliverable D2.1, "Requirements, use cases, and scenario specifications," June 2023. D45. TERRAMETA Deliverable D1.1, "Data management plan," June 2023. D44. RISE-6G Deliverable D6.3, "Network architectures and deployment strategies with RIS for enhanced EE, EMFEU, and SSE (Final Specifications)," June 2023. D43. RISE-6G Deliverable D5.3, "Control for RIS-based localisation and sensing (Final Specifications)," June 2023. D42. RISE-6G Deliverable D4.3, "Deployment and control strategies of RIS based connectivity (Final Specifications)," June 2023. D41. RISE-6G Deliverable D3.4, "Optimised RIS prototypes for PoCs and model assessment test," June 2023. D40. RISE-6G Deliverable D3.3, "RISE-6G RISE environment final model," December 2022. D39. RISE-6G Deliverable D8.3, "Intermediate dissemination and standardisation activity report," September 2022. D38. RISE-6G Deliverable D2.5, "RISE network architectures and deployment strategies analysis: First results," July 2022. D37. RISE-6G Deliverable D3.2, "RIS designs, and first prototypes characterisation," July 2022. D36. RISE-6G Deliverable D6.2, "Sustainable RIS solutions design for EE, EMFEU and SSE (intermediary specifications)," June 2022. D35. RISE-6G Deliverable D5.2, "Algorithms for RIS-based localisation and sensing (intermediary specifications)," June 2022. D34. RISE-6G Deliverable D4.2, "Multi-user techniques and connectivity of RIS based communication and mobile edge computing (intermediary specifications)," June 2022. D33. RISE-6G Deliverable D6.1, "Network architectures and deployment strategies with RIS for enhanced EE, EMFEU, and SSE (intermediary specifications)," May 2022. D32. RISE-6G Deliverable D3.1, "Preliminary RIS model and measurement campaigns," May 2022. D31. RISE-6G Deliverable D5.1, "Control for RIS-based localisation and sensing (intermediary specifications)," April 2022. D30. RISE-6G Deliverable D4.1, "Deployment and control strategies of RIS based connectivity (intermediary specifications)," April 2022. D29. RISE-6G Deliverable D2.4, "Metrics and KPIs for RISE wireless systems analysis: final results," February 2022. D28. RISE-6G Deliverable D2.3, "Reference system, scenarios and use cases analysis: final results," February 2022. D27. RISE-6G Deliverable D8.6, "Data Management plan," June 2021. D26. RISE-6G Deliverable D8.2, "Standardisation action plan," June 2021. D25. RISE-6G Deliverable D2.2, "Metrics and KPIs for RISE wireless systems analysis: First results," June 2021. D24. RISE-6G Deliverable D2.1, "Reference system, scenarios and use cases analysis: First results," June 2021. D23. RISE-6G Deliverable D8.1, "Dissemination and project website," April 2021. D22. WIDEBAND-HF Deliverable D3.4, "HF modem design and analysis: Progress report," May 2019. D21. WIDEBAND-HF Deliverable D3.3, "D-MIMO for the spatial degree of freedom: Progress report," May 2019. D20. WIDEBAND-HF Deliverable D3.2, "System architecture: Progress report," May 2019. D19. WIDEBAND-HF Deliverable D3.1, "Wideband HF channel models: Channel model analysis," May 2019. D18. WIDEBAND-HF Deliverable D2.4, "HF modem design and analysis: State of the art report," February 2019. D17. WIDEBAND-HF Deliverable D2.3, "D-MIMO for the spatial degree of freedom: State of the art report," February 2019. D16. WIDEBAND-HF Deliverable D2.2, "System architecture: API definitions and distributed frequency discovery progress report," February 2019. D15. WIDEBAND-HF Deliverable D2.1, "Wideband HF channel models: State of the art report," February 2019. D14. HARP Deliverable D1.3, "Year II: Annual scientific report," November 2014. D13. HARP Deliverable D4.1.1, "Transceiver techniques," November 2014. D12. HiATUS Deliverable D1.4, "Final plan for the use and dissemination of foreground," May 2014. D11. HiATUS Deliverable D1.8, "Year III: Annual scientific report," April 2014. D10. HARP Deliverable D1.3, "Year I: Annual scientific report," November 2013. D9. HiATUS Deliverable D7.1, "Year III: Compact antenna prototypes," September 2013. D8. HiATUS Deliverable D6.1, "Year III: Implicit and explicit CSI-based transceiver techniques," September 2013. D7. R3-COP Annual Report, "Underwater communication system," July 2013. D6. HiATUS Deliverable D1.5, "Year II: Annual scientific report," April 2013. D5. HiATUS Deliverable D1.2, "Year I: Annual scientific report," April 2012. D4. NEWCOM++ Deliverable DR.3.3, "AMC design towards next generation wireless systems," January 2011. D3. NEWCOM++ Deliverable DR.3.2, "AMC design for single- and multi-carrier wireless systems," January 2010. D2. NEWCOM++ Deliverable DI.4.1, "First release of the NEWCOM++ software simulation library, handbook, and suggested reference scenarios," June 2009. D1. NEWCOM++ Deliverable DR.3.1, "State of the art and research on AMC for concatenated coded multi-carrier systems and related technologies," June 2008.   Theses T3. G. C. Alexandropoulos, "Performance study of space diversity receivers over correlated fading channels," Ph.D. thesis, Computer Engineering and Informatics Department (CEID), School of Engineering (SE), University of Patras (UoP), Rio–Patras, Greece, June 2010; available online (in Greek). T2. G. C. Alexandropoulos, "Development and implementation of dominant source localization and tracking techniques in randomly distributed sensor networks," M.A.Sc. thesis, CEID, SE, UoP, Rio–Patras, Greece, October 2005; available online (in Greek). T1. G. C. Alexandropoulos, "ADPCM source coding implementation on TMS320C6711 digital signal processor," Dipl.–Comp. & Inf. Eng. thesis, CEID, SE, UoP, Rio–Patras, Greece, October 2003; available online (in Greek).